This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Trichomonad parasites, T. vaginalis (Tv) and T. foetus (Tf), cause major sexually transmitted diseases in human and cattle, respectively, and may predispose human patients to AIDS infection. BNS et al. purified lipophosphoglycan from both parasites an treated them with mild acid (trifluoroacetic acid) and different enzymes (endo-beta-galactosidase, another beta-galactosidase, phospholipase C) in order to obtain oligosaccharide structures short enough for MS/MS characterization. The fractions from Tv were initially characterized by MALDI-TOF MS, then the oligosaccharide portions were reduced and permethylated before analysis by LC-MS/MS, using the QoTOF mass spectrometer or the LTQ-Orbitrap MS system. A variety of sugars assigned to different structural motifs was identified. Many structures have been assigned and further data interpretation and investigation is ongoing. Biological characterization has shown that the T. vaginalis lipophosphoglycan triggers a selective upregulation of cytokines by human female reproductive tract epithelial cells. Several new samples of the lipophosphoglycan have been prepared for variants of the T. vaginalis. The structures are being determined by MALDI- and ESI-MS. LacNAc repeats are visible even in the MALDI-TOF mass spectra. Methods developed at the MS Resource for ETD of Glycans are being employed for sequence determinations.